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Dr Aseni Wickramatillake
Substance
Dose
Duration/chronicity
Individual degree of tolerance
Time since last dose
Person’s expectations as to the substances effect
Contextual variables
Underlying CNS changes that occur following repeated use of a drug such that the person develops tolerance and/or withdrawal
The need to use a greatly increase amount of a substance in order to achieve the desired effect OR
A markedly diminished effect being associated with continued use of the same amount of the substance
The degree to which tolerance develops varied greatly between drugs
Maladaptive behavioral change with physiological & cognitive effect that occurs
when concentration of a substance declines in the body
Alcohol = Ethyl alcohol or ethanol
Is not digested in the human body
Is absorbed directly from the stomach (20%) and intestines (80%) into the blood stream
Thereafter carried to every part of the body
Liver is responsible for eliminating the alcohol by CH3CH2OH (alcohol) H20 + CO2
Drunkenness occurs when drinking is > elimination by liver
Alcohol break down is slow. Approx: one unit per hour (however varies on the individual)
1 unit = half pint of beer / standard glass of wine or spirits
Alcohol is removed from the blood at a rate of approximately 15mg per 100ml per hour
15 mg/100ml /hour
Eg: 1 ½ pints of beer or 3 whiskies
▪ = blood alcohol level of 45-50 mg/100ml
▪ Excretion time= 45/15 =3-4 hours for blood alcohol level to normalize
Absorption rate is dependent on the type of drink (alcohol with fizzy mixes are more rapidly absorbed into the blood)
Body weight (reduced weight leads to greater effects)
Amount of food in the digestive tract (proteins will slow down processing of alcohol)
Individual metabolic differences
Alcohol elimination rate cannot be sped up
Black coffee, steam baths or fresh air will not change the rate of oxidation
Sleeping may actually prolong the rate of elimination due to slow body functions and slow metabolic rate
Eating during drinking will only slow the rate of absorption not the elimination
BAL (blood alcohol level) 0.08 or 1.0 g/dl- legal definition
Depressants slow the activity of the central nervous system (CNS)
Reduce tension and inhibitions
May affect judgment, motor activity, and concentration
Low doses ▪ Mood lability
▪ Impaired judgment
▪ Ataxia
At higher doses
▪ nystagmus
▪ slurred speech
▪ decreased concentration
▪ anterograde memory loss "blackouts".
Levels of impairment and concentration of ethyl alcohol in the blood:
BAC = 0.06: Relaxation and comfort
BAC = 0.09: Intoxication
BAC > 0.55: Death
▪ Most people lose consciousness before they can drink this much
Effects of alcohol:
a. Impaired judgment
b. Impaired ability to reason
c. Degraded muscular co-ordination
d. Lack of inhibition and self control resulting in increased recklessness
e. Degraded vision
f. Balance and sensory illusions
g. Disrupted sleep patterns (alcohol degrades REM sleep and causes early waking)
h. Heightened susceptibly to hypoxia i. Physical damage to the liver, heart, brain and
blood cells j. Disrupts short and long term memory k. Slow reaction time l. Allows the feeling that performance is
improved
High altitude, less oxygen, worsens effects Consumption above the following levels can
cause permanent damage to the body:
Men - 5 units daily 21 units per week Women - 3 units daily 14 units per week
Alcoholic is danger to himself/herself and others Alcoholics must admit to their alcoholism and
willingness to accept treatment is the most important element
Total abstinence is the only realistic goal as they cannot return to controlled drinking
High level of social drinking can be damaging even without alcohol dependence
No profession is exempted from the illness Some people often erroneously use alcohol to
unwind and as an sleep aid
“ when the excessive use of alcohol repeatedly damages a person’s physical, mental, or social life” WHO
Single most important characteristic of the alcoholic’s use of drink is a loss of control with a continuing progression to more and heavier drinking or regular binges lasting days or even weeks.
Alcoholics may not present the classic picture of a derelict existing on cheap wine or methylated spirits
Most are supposedly sober citizens with responsible jobs as doctors, lawyers, managers or even clergy
a. Drinking alone b. Gulping the first drink c. Preoccupation with the next drink d. Becomes defensive and angry when criticized
about the drinking habits e. Protection of the alcohol supply f. Use of alcohol as a tranquilizer g. Loss of memory of events when drunk h. Requirement to increase the intake to feel good i. Morning shakes j. High tolerance to alcohol k. Loss of control of drinking
Early
Anxiety
Irritability
Tremor
Decreased consciousness
Insomnia
As withdrawal continues
Delirium tremens (confusion, alternating level of consciousness, hallucinations, HTN, tachycardia, diaphoresis, vascular collapse) - usually appear within 72 hours after stopping
Seizures- within 48-72 hrs
CIWA (Clinical Institute Withdrawal Assessment for Alcohol)
Assigns numerical values to orientation ▪ Tremor
▪ Sweating
▪ Anxiety
▪ Agitation
▪ Tactile/ auditory/ visual disturbances
Benzodiazepines agonist of GABA and cross tolerant with alcohol reduce risk seizures
Anticonvulsants reduce risk of seizures, may reduce kindling, helpful for protracted withdrawal.
fetal alcohol syndrome (FAS): low birth weight, irregularities in head and face, intellectual deficits
Cognitive - support, education, skills training, psychological, group discussion
Medications
Disulfiram
Naltrexone
Acamprosate
Substances may cause temporary changes in behavior, emotion, or thought
Substance intoxication is a form of poisoning
Dose makes the Poison (Paracelsus)
Factors of substance abuse Sociocultural
Psychological
Biological
Abstinence with positive attitude
Experiment with friends – Peer pressure
Start use
Regular increasing to heavy use
Abuse
Control
A maladaptive pattern of use leading to impairment, in at least one of the following, occurring within a 12-month period:
recurrent substance use resulting in a failure to fulfill major role obligations at work, school, or home
recurrent substance use in situations in which it is physically hazardous
recurrent substance-related legal problems
continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance
A person relies on harmful or hazardous use of psychoactive
substances, including alcohol and illicit drugs excessively and repeatedly, impeding normal psychological and social functioning.
A maladaptive pattern of use, leading to impairment as manifested by three (or more) of the following, occurring at any time in the same 12-month period:
▪ Increased tolerance
▪ Withdrawal
▪ The substance is often taken in larger amounts or over a longer period than was intended
▪ There is a persistent desire or unsuccessful efforts to cut down or control substance use
▪ A great deal of time is spent in activities necessary to obtain the substance, use the substance, or recover from its effects
▪ Important social, occupational, or recreational activities are given up or reduced because of substance use
▪ The substance use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by the substance
Living in stressful socioeconomic conditions
Higher rates of unemployment correlate with higher rates of alcohol use
People of lower socio economic groups have higher rates of substance use in general
Abuse and dependence are more likely to appear in societies where substance use is valued or accepted
Behaviorists: operant conditioning may be significant in continuation of substance abuse. Temporary reduction of tension of the drug lead
to a rewarding effect
Increasing the likelihood to repeatedly seek similar reactions
Genetics may also play a significant role in
substance abuse (common among relatives)
Depressants
Stimulants
Hallucinogens
Cannabis
Polydrug use
Slow the activity of the central nervous system Reduce tension/anxiety and inhibitions
Slowed pulse, breathing and blood pressure
Poor judgment
Impaired motor activity/ coordination
Poor concentration and memory
Widely used depressants:
1. Alcohol
2. Sedative-hypnotic drugs
3. Opioids
Produce feelings of relaxation and drowsiness
low doses - calming or sedative effect
high doses - sleep inducers or hypnotics
Examples
Barbiturates
Benzodiazepines
Can be swallowed or injected
BARBITURATES
Consumed as a pill Low doses - reduce
anxiety, induce muscle relaxation and mild euphoria
Barbiturates are metabolized by the liver
Fatal in overdose (coma, respiratory–cardiac arrest)
BENZODIAZEPINES
Relieve anxiety Most popular sedative-
hypnotics: Xanax and Valium
Rarely fatal when taken alone
Slurred speech Impaired judgment Poor concentration Irritability Hostility Unsteady gait Excessive muscle relaxation of the diaphragm may cause
respiratory arrest
Withdrawal can cause delirium and seizures
1. Natural compounds – moderate dose leads to pain relief and induce sleep
a) Opium b) Heroin c) Morphine d) Codeine
2. Synthetic compounds - methadone
Collectively as “narcotics”
Each drug has a different strength, speed of action, and tolerance level
Can be injected, swallowed, smoked, snorted
• Opioids bind to the receptors in the
brain that ordinarily receive
endorphins a neurotransmitter
which relieve pain and reduce
emotional tension
Effects
pain relief
loss of inhibition
ecstasy
euphoria
drowsiness
nausea
poor coordination
constipation
confusion
sedation
respiratory depression and arrest
unconsciousness, coma, death
narrowing of the pupils
Opioids are often “cut” with noxious chemicals
(impurities)
Dirty needles and other equipment can spread infection
Clonidine(catapres) –suppresses opiate withdrawal symptoms
Can be use legally in medical treatment (pain relief)
Oxycodone (OxyContin, Percodan, & Tylox)
Hydrocodone (Vicodin, Zydone, and Lortab)
Heroin ▪ Rapid dependence, tolerance ▪ Significant withdrawal symptoms
▪ Anxiety and restlessness ▪ Muscle twitching, aches ▪ Fever ▪ Vomiting ▪ Weight loss
▪ Overdose ▪ Paralysis of breathing due to shut down the respiratory center
in the brain ▪ Death
▪ Withdrawal ▪ 6-24hr (Last up to 72 hours)
Types Amphetamine Cocaine Nicotine Caffeine MDMA (3,4-methylenedioxy-N-methylamphetamine) -Ecstasy Methamphetamine Ritalin
Use Injected Smoked Snorted Swallowed
Increase the activity of the central nervous system
Effects Increased heart rate and/or irregular heart beat Raised blood pressure Increased mental alertness Feelings of exhilaration Increased energy Heart failure Nervousness Insomnia Reduced appetite Weight loss
Derived from the leaves of the coca plant (alkaloid substance)
The most powerful natural stimulant
Around 3% of the population will become dependent on cocaine at some point in their lives
Use: freebase form – more expensive Crack a powerful form of freebase – rock crystal heated,
melted down for smoking in a pipe – cheaper than cocaine
Work by increasing dopamine at key receptors in the brain (mesolimbic areas) by preventing the neurons that release it from reabsorbing it
Increase norepinephrine and serotonin
Euphoric rush Pain reliever Increase sexual desire Increase self confidentiality ( can achieve
anything)
It stimulates the central nervous system and decreases appetite
Overdose can cause paranoia, hallucinations, insomnia, heart problems leading to death
Manufactured in the laboratory
Used in medical treatment
Stimulate the CNS by increasing dopamine, norepinephrine, and serotonin
Chronic use can reduce the volume of the hippocampus
Rapid tolerance and dependency
Serious depression and sleepiness on withdrawal Withdrawal within few hours
Increase alertness and motor activity
Reduce fatigue
Increased energy,
Sleeplessness
Decreased appetite
Increase heart rate
High-euphoric feeling
Hyper-activity/vigilance
Talkativeness
Grandiosity
Hallucinations
Anxiety
Repetitive behaviors
Anger
Irritability
Fighting/ hostility
▪marked dysphoria
▪fatigue
▪vivid & unpleasant dreams
▪hyper or insomnia
▪psychomotor act
Caffeine is the world’s most widely used stimulant
Around 80% of the world’s population consume it daily
Forms of Caffeine ▪ Coffee
▪ Tea
▪ Cola
▪ Chocolate
▪ Over the counter medication
More than 2 to 3 cups of brewed coffee can lead to caffeine intoxication
6-8 cups of normal strength a or coffee daily will lead to dependence
As little as 200 mg may reduce performance An average coffee drinker consumes 3.5 cups
a day (360-440mg) To be fatal, 10 g (100 cups) of coffee need to
be consumed (seizures and respiratory failure)
An intake of 25-30 cups a day is sufficient to show signs of altered physiological functions
Hear odd noises
See flashes of light or halos
Exhibit withdrawal symptoms
Extreme nervousness
Increased heart rate
Raised blood pressure
Caffeine is excreted from the urine and is a diuretic
a. Ulcers and other digestive disorders b. Increase risk of cardiac arrest c. Hypertension d. Personality disorders e. Chronic muscle tension f. Insomnia g. Disorientation h. Hyper-activeness (especially in children)
Usually occurs 12-16 hours after the last dose Irritability Sluggishness Headaches Depression Drowsiness Lethargy Occasional nausea and vomiting (in the most
serious case)
Tobacco – Nicotine Stimulates dopamine neurons in mesolimbic area 1 of 6 deaths related to tobacco use Commonly cause Lung cancer Other Effects Emphysema Cancers of larynx, esophagus, pancreas, bladder, cervix,
stomach Sudden infant death syndrome Pregnancy complications Cardiovascular disease
Known as psychedelic drugs Produce powerful changes in sensory perceptions Natural compounds
Mescaline
Psilocybin (extracted from Mushroom) Synthetic compounds
Lysergic acid diethylamide (LSD)
MDMA (ecstasy) Use
Swallow
Smoke
Increased body temperature Heart rate Blood pressure Loss of appetite Sleeplessness Numbness Weakness Tremors Altered states of perception
and feeling (flashbacks) Disrupted time perception
Nausea
Anxiety
Depression
Lability of mood
Paranoid delusions
Colourful Visual Hallucinations
Dilated pupils
Sweating
Blurred vision
Decreased coordination
Tolerance and withdrawal are rare Dangers
▪ experience of a “bad trip” – the experience of enormous unpleasant perceptual, emotional, and behavioral reactions
▪ risk of hallucinogen persisting perception disorder (“flashbacks”) –can occur long after last dose
Produced from varieties of the hemp plant
The major active ingredient in cannabis is tetrahydrocannabinol (THC)
Types Hashish- solidified resin of the tops of cannabis plant , stronger
than marijuana Marijuana - a mixture of buds, crushed leaves, and flowering tops
Use Swallow Smoke
Euphoria Slowed thinking and
reaction time Rapid emotional
changes Impaired memory and
learning Anxiety Panic attacks Confusion Impaired balance and
coordination
Cough and frequent respiratory infections
Damage to lung structure and functions (chronic users)
Increased heart rate and blood pressure
Increase appetite Dry mouth Blood shot eyes
Marijuana users can develop tolerance and withdrawal ( flu type symptoms and irritability)
Most widely used illicit drug Prohibited to be used in medical treatment High potency of the drug can cause
▪ Panic reactions similar hallucinogens
▪ Sensorimotor effects –increased accidents
▪ Poor concentration and impaired memory
SAMHSA, 2006 Substance Abuse and Mental Health Services Administration. (2007). Results from the 2006 National Survey on Drug Use and Health: National Findings (Office of Applied Studies, NSDUH Series H-32, DHHS Publication No. SMA 07-4293). Rockville, MD.
SAMHSA, 2006
Substance Abuse and Mental Health Services Administration. (2007). Results from the 2006 National Survey on Drug Use and Health: National Findings (Office of Applied Studies, NSDUH Series H-32, DHHS Publication No. SMA 07-4293). Rockville, MD.
Behavioral therapy Use of classical conditioning principles in
treatment
▪ limited success long-term when used alone
▪ can be helpful when combined with other approaches
Substance Abuse
Unpleasant Stimulus
Lose Craving
Biological medication
Antagonist drugs: Oppose the action of a neurotransmitter (Chantix for smoking)
Social therapy
Community prevention programmes
Self-help treatment programmes
Culture sensitive programmes
No single treatment for all Treatment should be readily available Treatment should attend to multiple needs of
the individual and not just the abuse Multiple methods of treatment may be
required Adequate duration of treatment for
effectiveness
Abstinence
Detoxification
Hospital Care Outpatient
Inpatient
Anonymous group/ individual therapy
Likely to happen if adequate treatment is not given
2/3 likely to relapse
Death due to suicide, homicide or accident or overdose
Communicable diseases and STDs such as HIV due to shared needles and unprotected sex
Illegal activities to obtain money for the supply of drugs Dealing drugs. theft, prostitution etc.
Exposure to infectious diseases via shared needles e.g. HIV Evidence suggests that free needles reduces
infectious diseases associated with IV drug use